Are you implying that, with current technology, we may expend more energy confining antimatter than we could derive from a controlled annihilation?
This is a book from 1988 by a favorite author Robert L Forward (the worst author from which I regularly bought books in hardcover; I just read them for the physics).
http://books.google.ro/books/about/Mirror_matter.html?id=GS4...
It was based on his report for NASA. I read the review: "He took the giggle factor out of antimatter"(!).
The main point was that if machines were built to create antimatter (instead of Nobel prizes), it wasn't so crazy to produce.
But as people are explaining to you, storage [of "large" masses like microgram] is still not solved. Afaik, at least.